Torches in different forms and for different applications have been known for several decades, with cylindrical torches of the kind mentioned in the introductory part having proven particularly preferred on account of the simple configuration, the ability to produce them in a cost-effective manner and the given stability. In addition to the shape, the possible functions of torches for different occupation groups have also expanded, these making different demands of the torches. In occupation groups such as for emergency services including the police and the fire brigade and in particular for railway conductors for example, torches which emit light in different colors in order to be able to communicate with colleagues by selecting the color are desirable.
For these reasons, torches which have LEDs of different colors and which can be switched on by means of a rotary switch are known in accordance with the prior art.
U.S. Pat. No. 7,722,209 B2 discloses, for example, a torch which has a rotary ring in the immediate vicinity of the torch head, the said rotary ring having magnets arranged in it and these magnets interacting with Hall probes which are arranged within the torch. Different LEDs and consequently different colors and/or intensities are activated depending on the set angular position.
A configuration of a rotary switch of this kind is highly complex and expensive to produce on account of the complicated components. In addition, these rotary switches are rapidly damaged in the event of robust use, and therefore problem-free functioning over a long period of time is not guaranteed.
An alternative and, in the process, robust and simple variant of a rotary switch is directly realized in the case of cylindrical torches by rotating the torch head or the end cap which are generally connected to the torch housing in a rotatable manner by means of a thread in any case. In the case of pressure switches of this kind, a contact element passes over different contact zones during rotation, this resulting in different electrical resistances or different LEDs being incorporated in the electrical circuit. One example of a rotary switch of this kind is disclosed by WO 2012/006977, according to which the rotary switch is formed by a rotatable ring on the end cap.
However, an embodiment of this kind has the disadvantage that the relative position of the contact elements which are arranged such that they can rotate in relation to one another is unclear as soon as the torch is unscrewed—for example in order to replace the batteries. When assembled, a clear angular position is no longer provided since threaded connections can be screwed together in different angular positions in relation to one another. As a result, the torch has to be switched on before each use in order to check whether the lamp lights up with the intended and set function. If a functional test of this kind is accidentally not carried out, misunderstandings or even severe accidents can be caused—depending on the field of application—since there is a big difference, for example, between a conductor transmitting a red signal or a green signal to the driver of his train.